BRAKES DISABLED by F/F's in RR INCIDENT:

From U.S.A. Today - 8:58 p.m. EDT July 8, 2013

This was an unfortunate 'chain of events' that resulted in a major castrophic event. I cannot blame the F/F's for their actions...not knowing that shutting-down the power to the engine(s) would result in the air-brakes to the entire train becoming disabled. I guess more information and training is neeeded on how to handle railroad fires / incidents.

"Volunteer firefighters in nearby Nantes had been called about 11:30 p.m. Friday to extinguish a blaze in one of the five locomotives, Fire Chief Patrick Lambert toldThe Montreal Gazette.

He told Reuters that firefighters had shut down the locomotive while they battled the fire, which was apparently caused by a broken oil or fuel line. But the train's crew had left the engine idling to keep the air brakes pressurized so the train wouldn't roll, said Ed Burkhardt, chairman of Montreal, Maine & Atlantic Railway."

This is a very long investigation that is just starting. There will be examinations of hand brakes, wheel flats, and the engines (which all seemed to have mysteriously disappeared from the wreckage). There are also conflicting reports on almost every aspect of this incident. We will know what happened in a year or two.

Apparently the railroad hasn't (or hadn't yet) been allowed on the scene, so if something is missing, it's not likely the RR took it. Even if they did, given the size and weight of such equipment, it's not like it could have been sneaked out of the area...

The locomotives apparently separated from the train when it derailed and travelled further down the tracks. There is conjecture that they were separated from the train by the FD, however.

In addition to questions about the firefighters and the brakes, there are questions regarding whether enough handbrakes were set on the consist. At minimum, at least ten of the cars should have had handbrakes set, plus all five locomotives.

Shutting down the locomotive that was running is easy, and from outside the cab. But that in and of itself shouldn't have allowed the train to move.

Questions have been raised as to why a train carrying 90+ cars of hazmat was left completely unattended.

While the FD did notify the RR, apparently the nearest RR employee knew zip about the equipment.

As HPA points out, the investigation is just beginning. We'll just have to be patient.

I'd wait too. The training we've had on RR engines would agree with what the FF's did. For the breaks to lose pressure.....something else was wrong.

Brakes on rail cars ENGAGE when they lose pressure. If an airline disconnects, the train will go into "emergency", and the brakes should engage.
Other than shutting down the engine on a locomotive or stabilizing cars so they don't move, Firefighters shouldn't be operating anything on the rail. That should be left up to the railroad or their contractors.
This is a good reminder that you should have emergency contact numbers for EVERY railroad in your run area, even mutual aid areas.

Brakes on rail cars ENGAGE when they lose pressure. If an airline disconnects, the train will go into "emergency", and the brakes should engage.

Brakes on rail equipment requires pressure to hold them ON 'sort-of'. If there is a loss of pressure, the brakes will release...unlike commercial vehicles (or fire apparatus) that pressure holds the brakes OFF. This is the reason, you must have air pressure to move a truck (with air brakes) just opposite of the railroad.

The Fire Dept. did everything 'by the book', but I think communications between the FD, the RR Dispatcher failed after the fire was extinguished, which is under investigation at present.

This is a recent article (July 8) that may help...as I am not too good anymore at explaining stuff. :-(

"Air brakes are supposed to be "fail-safe"... Or are they? How do air brakes work and what would cause them to fail?.

The brakes on the individual cars are applied using pressure from an air reservoir on each car. A reduction of pressure in the brake line (that hose you see running between the cars, plus) causes air to be released from the reservoir into the brake cylinder.

Air pressure from the brake line is used to recharge the reservoirs when the brakes are released.

If pressure in the brake line is quickly reduced to zero, the brakes will apply in "emergency."

If the pressure is reduced slowly, they'll apply slowly up to a point called "equalization."

If there is no air pressure in the reservoirs, the brakes will not apply at all, or will release. This is done intentially in railyards when the cars are sorted, in order to save time.

It occasionally also causes runaways, if the engineer applies the brakes too often and does not allow the reservoirs to sufficiently recharge. Eventually there is not enough air in the reservoirs to apply the brakes.

It can also happen due to leakage, the chief reason a locomotive was left running. Over time, all of the air may leak from reservoirs and the brakes will release for lack of air pressure. There is some doubt that this happened with this incident as it would be unusual for a whole train to leak off in the short timespan involved.

There is also a situation which will cause the brakes to release on their own. Too much to explain here.

Railroad air brakes are failsafe, to a point. That failsafe can be defeated.

The brakes on the individual cars are applied using pressure from an air reservoir on each car. A reduction of pressure in the brake line (that hose you see running between the cars, plus) causes air to be released from the reservoir into the brake cylinder.

Thanks tree68 for this 'professional, detailed' information'. Here is another 'interesting' article that I received today (Wed) that you might also find informative... :-)
"Engineer rushed to haul tankers away from crash", railway chair says"Montreal, Maine and Atlantic Railways chair Ed Burkhardt said the engineer found a Trackmobile, a vehicle that can pull several cars at a time, and went to the rear of the train.

He hooked up several cars, all the lightweight vehicle for hauling rail cars can pull, and moved them away from the wreckage, Burkhardt said.

He returned once more, pulling a total of nine from the disaster site, where explosions over the course of several hours killed a confirmed 13 people, with almost 50 still missing.

Tree68 has provided a very good start to understanding train (Westinghouse) brake system. There are in reality two different braking systems and three ways of applying train / locomotive brakes. On the locomotive there is an "Independent" brake system that applies ONLY the locomotives brakes. This independent brake requires air to APPLY the brake. Thus if the locomotive brakes are "SET" there must be continuous air pressure to force the brake shoes against the wheel or axle rotors. This is the normal way an engineer would secure a train. This method is routine, in that it is the normal way the crew would keep a train from rolling when the crew is in the vicinity. Train brakes (As tree68 describes) are released by applying air to the train. This air not only releases the brakes, but also fills reservoir tanks on each car. The pressure in each reservoir can be adjusted by means of "retainers" (air pressure regulators) ans so when the train brakes are applied to make a normal stop, the air pressure in the train is really bled down until the imbalance between "retained" air in each car's tanks is applied to one side of the diaphragm forcing the shoes into the wheels. The other side of the diaphragm has some train air remaining so that the amount of braking can be regulated by the engineer depending upon how much train air is bled down. Emergency application dumps ALL the train air, allowing all the retained air to push against a now unbalanced diaphragm and giving full braking on all cars. The third means of applying brakes is to manually "tie in" the hand brakes (hand wheel) on each car. There are regulations stating the duties of the crew when a train must be left unattended. A certain number of hand brakes must be set as required in the regulations. The problem here is the engineer was "Out of hours" and he was a one man crew. (Not current US regulations) If you have used the "independent" brake successfully 10,000 times a year, and it has been successful all 10,000 times......???? Why follow the letter of the law and set the hand brakes? This condition (non-cyclic) unusual occurance is exactly why the regulations were written. As said by others on here... The investigation will be interesting. If I had my bets, I would say that both the dispatcher and the engineer are going down the road. And there may be others who will recieve reprimands or dismissals as the repercussions occur.